Prohexadione calcium [calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate] is a known plant growth regulator. Prohexadione calcium is widely used for the regulation of shoot growth in apple trees. However, prohexadione calcium has been recognized as a plant growth regulator for use with agricultural crops including at least apples, pears, peaches, peanuts and grasses.
Prohexadione calcium is sold under the brand name APOGEE in the United States by BASF Corporation, Research Triangle Park, N.C., USA. APOGEE suppresses vegetative growth in apple trees, and thus reduces shoot growth. Infection of apple trees by the fire blight bacteria (Erwinia amylovora) is detrimental to apple yields and can even result in the death of the tree if left untreated. While antibiotics are known to treat fire blight infections, the bacteria may be developing a resistance to many antibiotics. To reduce the need for antibiotics, an alternative is to pro-actively manage the infection risk. Because tree shoots are new vegetative growth, their softer tissue is more prone to infection, Thus, by reducing shoot growth, infection risk is reduced, thereby reducing the likelihood that subsequent treatment will be necessary.
Calcium is one example of a valuable micronutrient, notably for fruits crops such as apples. However, BASF Corporation acknowledges that research has shown that calcium added to APOGEE will reduce its efficacy and therefore instructs that APOGEE not be tank mixed with calcium sprays. Thus, providing added calcium to the fruit crops in conjunction with prohexadione calcium use has resulted in separate applications of the micronutrient and plant growth regulator.
For the reasons stated above, and for other reasons which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternative approaches to providing micronutrients to plants in conjunction with prohexadione calcium-based plant growth regulators.